Time Lapse Video-week to week transition animation
That sounds like a really cool project, I'd be interested to see the results if you happen to post it somewhere.
As far as animating, if each stage of construction is a separate object, you can keyframe their visibility at different points along the timeline to have them transition.
For example, assuming 30 frames per second and each object stays in the scene for 2 seconds, you would start out the scene with the first object visible and the rest turned off (for rendering, not just in the viewport).  At frame 1, hold the cursor over the visibility icon for that object and press i to add a keyframe.  You'll want to have the other objects turned off and keyframe each of them the same way.  Notice that the color of the icons changes when they're keyframed:

Move the timeline to frame 60 (2 seconds) and keyframe Object 1 again, this will keep it visible for the entire two seconds.  Now, keyframe Object 2 as visible.  Move the timeline to frame 120 (0:04 in video time) and keyframe Object 2 as visible again and Object 1 as invisible.  Move the timeline to frame 150 (0:05 in video time) and keyframe Object 2 again to keep it visible.  I did a test in Blender with three objects and here's what the timelines looked like for all three:
Object 1:

Object 2:

Object 3:

The diamonds are the keyframes, the line in between them shows when the object is in a constant state (in this case, visible).
For the rest of the objects, keyframe them as follows:
-invisible at frame 0
-visible at the end of the last object
-visible 60 frames later
-invisible at the final frame
Doing that, you should be able to just keep increasing the total number of frames as you add more objects and, each time you add an object, just render only the new frames and assemble everything in your video editor of choice.  You can even add transitions between them, titles/captions, etc.
Good luck, hope that helps!